3rd International Workshop on Web Services and Formal Methods

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3rd International Workshop onWeb Services and
Formal Methods

• Report on WS-FM 2006, Vienna
• Andreas Duscher

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Content

• Key Data
• Topics
• Program
• Overview of Presented Papers

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WS-FM 2006

• held at Vienna University of Technology, during
  September 8-9, 2006
• in conjunction with the 4th International
  Conference on Business Process Management BPM
  2006
• Featured 15 papers selected among 40 submissions
• Three invited papers
• "... bringing together researchers working on Web
  Services and Formal Methods"Web Services and
  Formal Methods, Proceedings, Springer, September
  2006.

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WS-FM 2006

• Co-chairs of Program Committee
• Gianluigi Zavattaro, Mario Bravetti (University
  of Bologna)
• Chair of Organizing Committee
• Manuel Nùñez (University of Madrid)

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Topics

• Protocols and standards for Web Services (WS)
• Languages and description methodologies for
  Choreography, Orchestration and Workflow
• Coordination techniques for WS
• Semantic-based dynamic WS discovery
• Security, performance evaluation, and QoS of WS

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September, 8th
8.45 Start of registrations 9.15 Opening by the
chairs 9.30-10.30 Invited talk DecSerFlow
Towards a Truly Declarative Service Flow
Language 11.00-12.30 Session Service
Choreography Towards the Formal Model and
Verification of Web Service Choreography
Description Language Execution Semantics for
Service Choreographies Choreography Conformance
Analysis Asynchronous Communications and
Information Alignment
14.30-16.00 Session Security and performance
analysis Verified Reference Implementations of
WS-Security Protocols Application of Model
Checking to AXML System's Security A Case
Study Evaluating the Scalability of a Web
Service-based Distributed E-Learning and Course
Management System 16.30-18.00 Session Service
composition A formal account of contracts for Web
services A Formal Approach to Service Component
Architecture Analysis and Verification of Time
Requirements applied to the Web Services
Composition
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September, 9th
9.30-10.30 Invited talk SCC a Service Centered
Calculus 11.00-12.30 Session Service
orchestration Towards a Unifying Theory for Web
Services Composition Orc Features into Petri
nets and the Join Calculus From BPEL Processes
to YAWL Workflows
14.30-15.30 Invited talk Service QoS composition
at the level of part names 16.00-17.30 Session
Service discovery and invocation Semantic
Querying of Mathematical Web Service
Descriptions Computational Logic for Run-Time
Verification of Web Services Choreographies
exploiting the SOCS-SI tool Dynamic
Constraint-based Invocation of Web Services
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Semantic Querying of Mathematical Web Service
Descriptions

• Rebhi Baraka, Wolfgang Schreiner

• Motivation
• Mathbroker Framework (Registry and Querying
  Facilities for Mathematical WS)
• Querying for Mathematical WS only possible on the
  syntactic structure of MSDL documents
• Result
• Extension for semantic querying

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Semantic Querying of Mathematical Web Service
Descriptions
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A Formal Approach to Service Component
Architecture

• José Luiz Fiadeiro, Laura Bocchi (University of
  Leicester)
• Antónia Lopes (University of Lisbon)

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A Formal Approach to Service Component
Architecture

• Service Component Architecture (SCA)
• Set of industry specifications for building
  applications and systems
• Builds on open standards (e.g. Web Services)
• Initiated by major software vendors (IBM, Oracle,
  BEA, ...)

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A Formal Approach to Service Component
Architecture

• Motivation
• Describing mathematical semantics of SCA
• Uniform and general model of service
  behaviour,independent of languages and
  technologies
• Other approaches (WSMF, OWL-S) see services as
  blackbox
• Result
• Core set of primitives for interaction
• Language SRML-P that
• captures the essence of SCA modelling paradigm
• operates on a higher level of abstraction

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A Formal Approach to Service Component
Architecture
Business Role
Wire
External Interface (provides)
External Interface (requires)
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A Formal Approach to Service Component
Architecture

• Core set of primitives for describing interaction

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A Formal Approach to Service Component
Architecture

• Language SRML-P Business Role Supplier

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A Formal Approach to Service Component
Architecture

• Language SRML-P Business Protocol Warehouse

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Dynamic Constraint-Based Invocation of Web
Services

• Diletta Cacciagrano, Flavio Corradini, Rosario
  Culmone, Leonardo Vito
• (University of Camerino)

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Dynamic Constraint-Based Invocation of Web
Services

• Motivation
• Web Service Description Language (WSDL)
  describes a collection of methods and their
  parameter signature, together with information
  about parameter syntax
• no dynamic constraints about invocation
  parameters can be expressed
• ontologies are not suitable for only describing
  constraints
• Result
• Enriched WSDL documents, that specify static and
  dynamic integrity constraints
• Software framework that consists of several open
  source technologies

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Dynamic Constraint-Based Invocation of Web
Services

• Enriched WSDL
• CLiX (Constraint Language in XML)
• based on First-Order-Logic and XPath
• simple and syntactic approach
• ltitemsgt
• ltitem id"1"gt
• ltprice currency"EUR"gt224lt/pricegt
• lt/itemgt
• ltitem id"2"gt
• ltprice currency"YEN"gt8432lt/pricegt
• lt/itemgt
• lt/itemsgt
• ltclixforall var"price" in"/items/item/price"gt
• ltclixequal op1"price/_at_currency"
  op2"'EUR'"/gt
• lt/clixforallgt

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Dynamic Constraint-Based Invocation of Web
Services

• Software framework
• OpenCLiXML (validates CLiX expressions)
• WSDL2Java (generates client stubs)

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Conclusion

• In particular
• A Formal Approach to Service Component
  Architecture
• declarative approach for describing service
  interactions and component models
• Dynamic Constraint-Based Invocation of Web
  Services
• a combination of existing software frameworks
• a new (not ontology-based) approach
• Generally
• a lot of interesting talks and nice people
• http//www.cs.unibo.it/projects/ws-fm06/